1. Field of the Invention
The present invention relates to a reproduction apparatus and a method for use with a recording medium, and more particularly to a reproduction apparatus and a method for use with a recording medium on which sub-data is recorded in association with main data such as audio and/or visual data.
2. Description of the Related Art
Currently, compact discs (CDs) and digital versatile discs (DVDs) have become widespread as digital video and audio media. Technological development has been made to improve capability and performance of the media for a next-generation packaged medium.
Sub-data is recorded in association with main data such as audio or visual data on the DVD or the CD-text disc in addition to control data related to the contents of the discs.
More particularly, the CD-text disc has the control data (i.e., Q channel data) and the sub-data (i.e., text data) recorded in the sub-code region of a TOC (Table of Contents) region in addition to the main data (i.e., audio data). Thus, it is necessary to read the control data and the text data to reproduce the CD-text disc. It takes a few seconds to read the control data of the CD-text disc and the maximum amount of the text data of 2048 packs (in a case of MODE4). Therefore, a user of a reproduction apparatus had to wait a long time for appearance of the text data on a display device. Moreover, it is impossible to start reading the main data such as music data until the control data and the text data is completely read or loaded. Thus, this causes a problem of requiring a long time for the completion of set-up until the main data is reproduced.
Furthermore, take as an example a disc-changer reproduction apparatus having a plurality of recording media loaded thereon and reproducing the media sequentially while replacing the media one after another. In this case, it was necessary for the apparatus to read the control data or the text data every time the recording medium is replaced. This made it difficult to improve various functions and performances such as a displaying speed of the text data as well as display control or reproduction control during the replacement of the recording media.
In addition, it takes time to read and decode compressed data when the sub-data such as audio data or sub-picture data is read before the main data or video data is reproduced in a case of the DVD video discs. This made it difficult to improve various functions and performances of reproduction apparatuses.
The present invention has been developed in view of the above-mentioned problems. An object of the present invention is to provide a method and a reproduction apparatus which can realize high-speed reproduction control of a recording medium and improved function and performance.
To achieve the object, according to the present invention, there is provided a reproduction apparatus for use with a recording medium on which sub-data is recorded in association with main data, which comprises a reading device for reading the sub-data from the recording medium, a memory for storing the sub-data, a data discriminator for determining whether a piece of sub-data read from the recording medium, which is at least one portion of the sub-data, is included in stored data already stored in the memory, and a controller for stopping the reading device from reading the sub-data when the data discriminator determines that the piece of sub-data is included in the stored data.
According to another aspect of the present invention, the controller controls so as to perform reproduction of the recording medium in accordance with the stored data when the data discriminator determines that the piece of sub-data is included in the stored data.
According to the present invention, there is provided a method of reproducing a recording medium on which sub-data is recorded in association with main data, which comprises the steps of reading the sub-data from the recording medium, storing the sub-data, determining whether a piece of sub-data read from the recording medium, which is at least one portion of the sub-data, is included in the stored data, and stopping reading the sub-data when the piece of sub-data is included in the stored data.
According to another aspect of the present invention, reproduction of the recording medium is performed in accordance with the stored data when the piece of sub-data is included in the stored data.